Attachment plug



March 16,1926. 1,577,348

s. MCCLATCHIE ATTACHMENT PLUG Filed July 24, 1920 97 tea/em Patented Mar. 16, 1926.

UNITED STATES V 1,5713% PATENT OFFICE.

STANLEY MoCLATCI-IIE, OF CAMBRIDGE, MASSACHUSETTS, ASSIGNOR TO BENJAMIN ELECTRIC MANUFACTURING COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

ATTACHMENT PLUG.

Application filcd July 24, 1920.

To all whom it may concern.

Be it known that I, STANLEY MoCLArcr-rln, a citizen of the United States, residing at Cambridge, in the county of Middlesex and State of Massachusetts, have invented new and useful Improvements in Attachment Plugs, of which the following is afull, clear concise, and exact description, referencebeing had to the accompanying drawings, forming a part of this specification.

My invention relates to electrical connector devices and more specifically to swivel attachment plugs.

One of the objects of my invention is to provide a swivel attachment plug which will be durable and eflicient in use, easy to wire, simple in construction and cheap to manufacture.

Further objects will appear from the detailed description to follow and from the appended claims.

In the drawings in which an embodiment of my invention is shown;

Fig. 1 is an axial section of a swivel attachment plug;

Fig. 2 is an axial section on the line 22 of Fig. 1;

Fig. 3 is a top plan view of the plug;

Fig. 4 is a transverse section on the line 4--4 of Fig. 1; and

Fig. 5 is a top plan View of the insulating base or body.

Fig. 6 is a perspective view of this base r or body.

The swivel attachment plug shown comprises in a general way, a shell contact 10, a center contact screw 11 (which also serves as a binding screw) a wiring terminal 12 for the shell contact 10, an insulating base 14 for supporting and insulating the con tacts 10 and 11 and wiring terminals, and an insulating handle or thumbpiece 15 securred to the threaded shell contact 10. The threaded shell contact 10 is swiveled with respect to the wiring terminals 12 and 13 so that the plug can be screwed into a socket without twisting the cords secured to the wiring terminals.

Referring now more in detail to the construction, the wiring terminal 12 for the threaded shell contact comprises a U-shaped sheet metal stamping 16, which embraces a portion of the cylindrical insulating base 14, and a binding screw 17 which extends Serial No. 398,689.

through the upper arm of the U-shaped stamping-and is threaded into the lower arm The base 14 has a notch 14 which accommodates the screw 17 The lower arm 18 of the U-shaped stamping engages a shoulder portion 19 of the threaded shell contact 10, so as to form a sliding electrical contact therewith.

The insulating base 14 is normally held in place in the threaded shell contactlO in a unique manner as follows:

The threaded shell contact 10 is provided with an inwardly-extending annular beaded portion or flange 20, beneath which a crescent-shaped flange 21 (Figs. 1, 3, 5 and 6) of the insulating base 14 may be positioned, this crescent-shaped portion and the member 16 looking the base in place, the member 16 having somewhat the 'function of a movable latch member.

Referring further to the latching function of the member 16, when the binding screw 17 is removed, this latch. member can be moved over into the notch 14 of the base 14 so that the inwardly extending bend 22 can disengage itself from the inwardly-extending shoulder 20 of the threaded shell contact to permit the base to be lifted out of the threaded shell, of if the screw 17 be only partly removed, the base may swing upwardly about the crescent-shaped projection 21 as a sort of hinge. This swinging movement of the insulating base 14 can be continued until the lower right hand edge of the U-shaped member 16 will clear the upper edge of the threaded shell contact 10, when the entire base can be slipped laterally to completely disengage the base from the threaded shell contact 10. When, however, the binding screw 17 is threaded into the U-shaped member 16, this U-shaped member is held in latching position to prevent the insulating base 14 from being withdrawn from the threaded shell contact 10. The U- shaped contact member 16 is prevented from becoming completely disengaged fro-m the insulating base by means of a pair of lugs 23 which extend toward each other, and embrace a portion of the base 14 and prevent the U-shaped member 16 from being withdrawn laterally.

The combined center contact and binding screw 11 is threaded into a sheet metal yoke-member 24, the ends of which are embedded in the insulating base 14, the central portion 25 serving as a binding: plate. The upper arm of the U-shaped sheet metal member 16 serves as a binding plate for the binding screw 17.

The insulating handle or thuinbpiece 15 may be permanently secured to the threaded shell contact 10, since in wiring the plug it is not necessary to disconnect the thumbpiece and contact. Neither is it necessary in wiring the plug to take the insulating base 1-1 out of the threaded shell Contact 10, as the wire can be inserted up through the central opening 25 off the insulating base 145 and secured underneath the heads of the binding screws 11 and 17- In screwing the plug into a socket the wires are not twisted as the insulating base 14: has a swivel connection with respect to the threaded shell contact 10.

lVhat I claim as new and. desire tosecure by Letters Patent of the United States is:

1. An attachment plug comprising a cylindrica-l insulating base having a central opening therethrough, a yoke-shaped metal member straddling said opening, a center contact threaded into the central portion of said yoke and forming a binding screw and a side contact insulated from said center contact by said cylindrical insulating body.

2. A swivel attachment plug comprising a binding screw, a threaded shell contact swivelcd with respect to said binding screw, an insulating base for supportin. said bind ing screw. and a U-shaped inztal member en'ibracin'g a portion of said insula='ing base and having a binding plate portion for cooperating with the head of the binding screw, and a sliding contact portion cngaging said threaded shel contact, said binding screw extending through a hole in the binding plate portion and being threaded into said sliding contact portion.

In witness whereof, I have hereunte subscribed my name.

STANLEY McCLiiTCl-Elll. 

